Differential timing device



Sept. 25, 1928.

R. LA FRANCE DIFFERENTIAL TIMING DEVICE Filed April 14, 1926 2 Sheets-Sheet 1 FIE-l"- INVENTUH Sept. 25, 1928. 1,685166 R. LA FRANCE DIFFERENTIAL TIMING DEVICE Filed April 14. 1926 2 Sheets-Sheet 2 IIE 2 l Ii 7 45 ITE- 5 g INVENTUH Patented Sept. 25, 1928.

UNITED STATES RICHARD LA FRANCE, OF TOLEDO, OHIO.

DIFFERENTIAL TIMING DEVICE.

Application filed April 14, 1926. Serial No. 101,922.

My invention is an improved differential timing device and is particularly adapted for use in conjunction with glass forming apparatus or similar apparatus, including several simultaneously operating mechanisms, one of which from time to time requires variation of its period of operation with respect to that of other associated mechanisms. V

In glass forming apparatus, for instance, it is customary to employ a forming machine comprising a continuously rotating mold carriage having a series of molds which pass in succession beneath a glass feeding device. The latter is operated in synchronism with the movements of the molds to deliver and drop a charge or gob of glass into each mold as the latter is passing. The glass feeding mechanism may include a plunger reciprocating within the glass over a discharge outlet in a furnace forehearth or boot, and shears for severing suspended charges of glass. As the molds pass the charge receiving position without any interruption in their movement, they are only in such receiving position for an instant and it is, therefore, important that the instant of dropping the charge of glass be accurately timed with respect to the movement of the mold past the charging station.

In practice, variable conditions are met which make an adjustment of such timing necessary. For example, changes in the speed of the mold carriage, variations in temperature conditions or fluidity of the glass, adjustments of the feeder for counteracting variations in the size of the charges being delivered, or for changing the size in order to make ware of a different size, and other variable conditions, require some provision for adjustment of the time relation between the operation of the feeder and the movements of the molds. It is also important to be able to time to a nicety the instant of drop-ping the charge to the mold. Any provision requiring the machine to be stopped to permit such adjustments is unsatisfactory, as any interruption in the operation of the machine is obviously objectionable and, further, because in making such adjustments when the machine is at rest, the operator has to guess at the required amount of change, with the result that he often has to make several attempts to get a satisfactory adjustment, and after each attempt must start the machine fore being able to tell whether the best timin relation has been obtained. As a further result, the operator will frequently be satisfied to allow what he considers to be well enough alone and therefore, operate with an inaccurate timing.

The present invention is designed to overcome the above difficulties and objections and provide a timing mechanism which can be readily adjusted while the machine is operatmg normally, permitting the operator to observe the effect of such adjustments and thereby obtain an accurate timing to suit conditions. The invention provides means for adjusting the timing to a nicety and permits such adjustments to be made at frequent intervals, as is often necessary to meet the frequent variations in practical operating conditions.

Other objects will be apparent hereinafter.

In the accompanying drawings:

Fig. 1 is a diagrammatic view of a rotatable glass forming machine and glass feeding apparatus with my timing deviceshown associated therewith.

Fig.2 is a top plan view of the timing de vice with portions shown in section.

Fig. 3 is a vertical central sectional view with parts in elevation, showing the relation of the adjusting devices within the housing.

While my improved differential timing device may well be employed in conjunction with many types of mechanisms, I have for the purpose of the present application and as illustrative of the particular application at present desired, shown the device, in association with a glass forming apparatus. The apparatus in this instance, includes a rotary mold carriage 5 carrying an annular series of blank molds 6, with which are associated the usual or any preferred form of funnel guides 7. The mold carriage is continuously rotated by means of a motor 8 or other form of prime mover having a shaft 9 extending therefrom and carrying a bevel gear 10 running in mesh with a bevel gear 11 which is fixed to the lower end of a shaft 12, the upper end of the latter mounting a pinion or spur gear 13 which runs in mesh with an annular or ring gear 14, fixed to the lower portion of the mold carriage. It will thus be seen that operation of the electric motor 8 will effect continuous rotation of the mold carriage 5, and by reason of such continuous rotation, cause the blank molds 6 to pass beneath the outer end of a feeder boot and successively register with a" submerged discharge orifice 21 formed inthe lower wall or floor of the boot. This boot 20, as is custom ary, receives its supply of molten glass from a furnace 22. A reciprocating plunger 23 extends downwardly into the molten glass within the boot 20 and is vertically aligned with the axis of the discharge orifice 21., The

' ments.

upper end of this flow regulating plunger 23 has link connection with a lever 24 which is fulcrumed between its endsby means of a cross or fulcrum pin 25, to a forwardly extending bracket or arm 26 spaced above the boot 20 and supported by a portion of the furnace 22. This bracket or arm 26 also carries a continuously rotating cam 27'whose face contacts with a cam roll 28 fixed to the adjacent end of the aforementioned lever 24. The contour of the cam 27 is of such form that with each cam revolution, the lever 24 moves on its fulcrum pin 25 and in turn causes the flow regulating plunger 23 to move downwardly and effect the expulsion of a gob or charge of glass through the discharge orifice.

In proper. timed relation to the movement of the flow regulating plunger 23 and essentiallyat the period it moves upwardly for necking inportions of a suspended gob or charge, severing means 29 are actuated to cut the suspended portion of the glass at the necked inpoint. 3

As has been previously stated, it is frequently desirable and necessary, because of the production of different sized ware and consequent issuance of different sized gobs of molten glass from the .boot, and for other reasons, to vary the timed relation between the periods of downward or expelling movement of the plunger 23, actuation of the severing means, and register of succeeding blank molds with the last two named ele- It is quite obvious that formation of a large suspended charge necessitates an advance of the period of expelling impulse of the plungb er so that the charge will be completely formed and severed simultaneously with register of a mold and the discharge orifice 21.

Continuous rotation of the cam 27 which causes periodic reciprocation of the flow control plunger 23,,is effected by a sprocket chain 35 runningover a sprocket wheel (not shown) at oneend of the cam shaft 27 This chain 35 is also trained over a sprocket wheel 36 fixed to one end of a shaft 37, carrying a driven helical gear 38 running in mesh with and driven by a driving helical gear 39, which is rotated continuously by'a shaft 40 having a bevel gear 41 running in mesh with suspended from the walls of the outlet, it is apparent that c an advance of the time of downward movement on the part of the reciprocating flow control plunger 23, will cause expulsion of glass, and formation and severance of gobs or charges in more nearly perfect timed relation to positioning of the blank molds forreception of the charges. In order that perfect timed relation in operation of the several mechanisms may be attained as above indicated, I providemeans for axially shifting the helical drive gear. 39 while in mesh with the driving helical gear 38, with the result that this last named gear.38. is caused to move circumferentially to a position in advance of or behind that occupied prior to the axial shifting of the drive gear 39. In other words, the normal point of contact of the driven gear 38 is advanced or retarded circumferentially with respect to a corresponding point of the drive gear 39. It.

is evident that such rotation on the part of the driven gear 38 changes its'former relation tothe driving gear and. driving shafts as stated, and by reason of the sprocket chain and cam connection of this driven gear to the reciprocating flow control plunger 23, the

period of operation of this flow control plunger is correspondingly changed with respect to the positions assumed by the blank molds 6.

As will be noted by reference to Figs. 2 and 3, my device, including the two named helical gears, comprises a sectional housing 45 in transversely aligned walls of which are formed bearings 46 supporting the opposite end portions of the aforementioned shaft 37. As shown, suitable packing glands 47 are arranged at the outer ends of the bearings for well known reasons. In this instance, the

driving gear 38 1s fixed rigidly to and for rotationwith the transverse shaft 37. The,

drive gear 39 is splined to a relatively short vertical shaft 48 whose ends are suitably journalled in vertically spaced bearings 49 at the upper and lower ends of the housing sec tions. The lower end of this shaft 48 has driving connection with the shaft 40 by means of a coupling 50, which facilitates ready removal of the timing device from the power transmitting system and replacement when desired.

\ While other devices may well be employed to effect axial shifting of the helical drive gear 39 on its shaft 48, I prefer to employ a yoke 55 which embraces the ends of the drive bearings 57 at its opposite ends slidably receiving the gear carrying shaft 48 and serving to maintain the yoke, gear and'adj usting screw in proper relation to each other. This yoke is formed with a longitudinal tapped bore 58 arranged in parallelism with the axis of the shaft 48 and gear 39 and is engaged with the threaded adjusting screw 56 whose ends are journalled in bearings 60 formed in the upper and lower ends of the housing. An operating handle or crank 61 is fixed to the upper end of the adjusting screw 56 so that an operator may readily adjust the yoke and driving gear to retard or advance position of the driven gear 38. It will be noted by reference to Fig. 3, that the threads on the adj usting rod 56 are of such size and pitch that vibration due to continuous rotation of the gears, shafts, etc., will not cause accidental rotation of the adjusting screw and consequent inaccurate relative positioning of the gears and associated parts. Further, the particular thread formation quite obviously greatly facilitates fine adjustment.

In employing this timing device in connection with glass working apparatus as herein disclosed, it is customary to arrange the device in proximity to the bottom of the glass feeding boot 20, and attach the housing 45 to a portion of the furnace 22 in any preferred manner.

As is understood in view of the foregoing description, the timing device, when employed in conjunction with glass working apparatus including a rotary mold carriage mounting an annular series of blank molds adapted to successively register with a glass discharge orifice through which glass is expelled by a reciprocating flow control plunger, is adapted by rotation of the control handle 61 to advance or retard the period of the glass expelling impulse of the plunger with respect to the periods of registration of the blank molds with the discharge orifice.

In the event formation and severance of gobs takes place slightly in advance of registration of a mold with the discharge orifice, the control handle or crank 61 is rotated to cause lowering of the driving gear 39 on its shaft 48 and consequent circumferential backward'shifting or retardation of the normal point of contact of the driven gear 38 with respect to a corresponding point of the driving gear. Such shifting of this driven gear 38 in turn causes a corresponding degree of backward movement on the part of the cam 27, and consequently delays to a greater or lesser degree, as circumstances may require, the period of expelling impulse by the flow control plunger 23. It is quite evident that through reverse rotation of the handle 61, an advance of the period of actuation of the flow control plunger 23 with respect to a definite periodic positioning of a given blank mold, may also be effected.

gear and helical driven gear running in mesh with each other, a yoke embracing the ends of the driving gear, and screw means for cffecting unitary axial movement of the yoke and driving gear to advance or retard the normal point of contact of the driven gear circumferentially from the corresponding point of the driving gear.

3. The combination of a helical driving gear and helical driven gear running in mesh with each other, a yoke embracing the ends of the driving ear, and an adjusting screw parallel with tie axis of said driving gear and engaging said yoke to permit axial adjustment of said driving gear and cause advance or retardation of the normal point of contact of the driven gear with respect to the corresponding point of the driving gear.

4. The combination of a helical driving gear and helical driven gear running in mesh with each other, an adjusting screw parallel with the axis of the driving gear, and means actuated by rotation of the screw to cause axial movement of the driving gear to advance or retard the normal point of contact of the driven gear with a corresponding point on the driving gear.

5. A device of the character described comprising a housing having relatively angularly isposed pairs of bearings in its walls, shafts mounted in said bearings and having portions extending beyond the housing for drivmg connection with extraneous mechanisms, a helical driven gear fixed for rotation with one of said shafts, a helical driving gear splined to the other shaft and running in mesh with the driven gear, and manually rotatable means for shifting the driving gear axially of its carrying shaft to circumferentially retard or advance the normal point of contact of the driven gear with respect to a corresponding point on the driving gear.

A device of the character described comprising a housing having relatively angularly disposed pairs of bearings in its walls, shafts mounted in said bearings and having portions extending beyond the housing for driving connection with extraneous mechanisms, a helical driven gear fixed for rotation with one of said shafts, a helical driving gear splined to the other shaft and running Ila in mesh with the driven gear, an adjusting screw arranged parallel with the driving gear axis, and connection between the adjusting screw and driving gear permitting longitudinal axial movement of the driving gear with rotation of the adjusting screw whereby to circumferentially retard or advance the normal point of contact of the driven gear with a corresponding point of the driving gear.

7. A device of the character described comprising a, housing having relatively angularly disposed pairs of hearings in its walls, shafts mounted in said bearings and having portions extending beyond the housing for driving connection with extraneous mechanisms, a helical driven gear fixed for rotation with one of said shafts, a helical driving gear splined to the other shaft and running in mesh with the driven gear, an adjusting screw arranged parallel with the driving gear axis, and a sliding yoke forming a connection between the adjusting screw and driving gear permitting longitudinal axial movement of the driving gear with rotation of the adjusting screw whereby to circumferentially retard or advance the normal point of contact ofthe driven gear with a corresponding point of the driving gear.

Signed at Toledo, in the county of Lucas and State of Ohio, this 12th day of April, 1926.

RICHARD LA FRANCE. 

